Three adults and one child remain hospitalized after the crash.
Athletics spokesman Rich Moser says strength coach Eric Cash and his wife, and Hoover's wife Penny are in stable condition at a Champaign hospital.
Two children have been released from the hospital, and one child is being held for observation. It was not immediately clear whose children they are.
A university spokesman says the assistant coach was traveling Saturday in a car with another staff member and family. The car apparently swerved to avoid a deer and crashed.
The accident happened down state in Effingham, Ill., which is southeast of Springfield.
Earlier in the day, Hoover had coached a playoff game against Southern Illinois University.
Hoover was in his third season as Eastern Illinois' offensive line coach. He had previously worked at Portland State University.
Earlier this month, an assistant coach for the women's basketball team died suddenly during a workout.
(The Associated Press contributed to this report.)
